The integrated circuit package is the building block used in a high performance electronic system to provide applications for usage in products such as cell phones, surgical equipment, military devices, surveillance devices, space telemetry devices, and a vast line of other high performance products that require small compact. The integrated circuit such as a chip or die contains circuitry that is designed to function in a high performance electronic system. Products having small dimensional requirements rely on limited sized integrated circuit packages with multiple chips or dice to excel in a continually expanding competitive global market.
The integrated circuit package having multiple chips commonly consists of a package base or package substrate, providing a mounting structure on which at least one chip or die is attached and having an enclosure such as an epoxy to protect its contents. The chip or die, a piece of semiconductor material has one side mounted or typically bonded with an electrically insulating and thermally conductive adhesive to the package base or package substrate.
The other side of the chip or die, referred to as an active surface of the chip or die, has electrically conductive areas or bond pads that provide for electrical connections to its circuitry. Leads, consisting of electrically conductive material, attach to the conductive areas or bond pads to provide electrical connection between the circuitry of the chip or die and other circuitry not of the same chip or die.
The other circuitry can be from one of three possible sources. The first possible source can be circuitry resident within the integrated circuit package, such as from another chip, indicative of a multiple chip integrated circuit package. The second possible source can be of circuitry residing outside the integrated circuit package such as from a printed circuit board within the electronic system.
Finally, the third possible source can be circuitry from one or more separate integrated circuit packages having one or more chips or dice within it. The separate integrated circuit packages, connected with the leads, can be enclosed together resulting in a single sealed package structure such as a Package In Package (PIP) or can form individually sealed packages attached by leads, such as a Package On Package (POP).
Clearly, the two most prevalent choices for product designers in need of performance circuitry within a small form factor product require extensive use of PIP or POP. The POP has advantages over the PIP due to reduced manufacturing processing and costs since it does not require an additional step to enclose or cover multiple separate packages into a single package.
The POP also provides the product designer with the capability of exchanging or upgrading one or more individual package during the lifetime of the product, unlike the PIP, which would need to be entirely redesigned.
There exists an industry demand for a POP solution providing lower costs, high manufacturing throughput, small form factor, and design flexibility. Those of ordinary skill in the art are aware of POP benefits, which include component reduction from fewer circuit boards and parts contributing to lower costs and the competitive advantages of responsive time-to-market and continuous flow (build on demand) manufacturing techniques enabled by high manufacturing throughput.
Also, those of ordinary skill in the art are aware of the importance of leverage and flexibility provided with POP through package substitution such as package swapping to improve costs, features, or performance by replacing package components as needed. Attempts have failed to provide a complete solution addressing simplified manufacturing processing, smaller POP dimensions, lower costs due to design flexibility and leveragability, and increased electrical wire connectivity capabilities.
In view of the ever-increasing commercial competitive pressures, along with growing consumer expectations and the diminishing opportunities for meaningful product differentiation in the marketplace, it is critical that answers be found for these problems.
Solutions to these problems have been long sought but prior developments have not taught or suggested any solutions and, thus, solutions to these problems have long eluded those skilled in the art.